Fluid pressure brake



' Jan. 1, 1935. GOOD 1,986,472

"FLUID-PRESSURE BRAKE Filed Oct. 13, 1930 INVENTOR JOHN N. GOOD BY g ATTORNEY Patented Jan. 1, 1935 John N Good; ,lwillnerding, Pa", .ass'ignor toThe Westinghouse Air-Brake Company,"Wilmerding,

Pa.', a corporation of Pennsylvania. An plicationioctolier is, 1930, Serial No. 488,268 s cla s ra ses- 59) This invention relates to fluid pressure brakes and more'particularlyto a valve mechanism for controlling the brakes ona car ofa train.

An object of the invention is to provide an 5 improved brake controlling valve mechanism of the type in which the means for controlling the communication through which fluid unoer pressure is supplied from a main reservoir to -the brake cylinder is controlled b-ya service application 'val-ve mechanism when a service rate of reduction in brakepipe' pressure is efiecte'd' and by an emergency application 'vaIVe in-echanism when an' emergency rate of reduction in 'braike pipe pressureisefieoted. v Another object of the invention is to provide an improved valve mechanism of the character mentioned whioh'is simple in construction, and reliable and exact in f unction under' all ;oondi tions of service. r i 3 20 useful improvements in the "construction, airrangement and combination of the severalfpartsof which it is composed, as wnrb 'hereinaaer more 'fully described andclaimed; V In the accompanying drawing; Figured is a diagrammatic view, mostlyinsection, of a fluid pressure brake equipment embodying th ve tion, showing the same" in releasepositionj Fig? 2 is a fragmentaryview or the emergencyapplie 30 cation portion of the equipment; showing the same in emergency position] F In the usualfluid pressure brake {equipment employing a *brakeppip auxiliaiy reservoir,

brake cylinder, and triple valve device, the [fluid under pressure for charging the auxiliary lieserr voir is supplied throughthefbrake pipe and a feed groove around the triple valve piston when the brakes are being released; and when the brakes are .being applied, there is often aisligh't back flow of "fluid under pressure from othe auxiliary reservoir to thefl'brake pipe through said feed groove. It is thus obvious thata-considerable amount of fluid underpressure is trans? mitted through the brakeplpe in applying and 55 body @ortioniin the form of a -pipe bracket, and

The invention also com-prises oertairrnew and r guiding the pin-63 and diaphragm releasing the "brakes; which tend "to retard the said pipe bracket is provided with a service application valve "device 10, an emergency applica tion' valve device 11, a relay valve device 12, and a-t-heck valvle device 13 which are all a part of the con'trol-ling valve device 6. l

A*=pipe 14;,extendingthroughout the length of the "train, is connected to the .main reservoir 8 on each car, by a pipe 15 provided waha choke 16. Through the pipe'l i the main reservoirs are adapted to be maintained equal.

The service application valve device 10 comprises-a casing divided'into sections 17, "18 and 191 interposed between the -section 1-7 and a cover plate 20 is a flexible diaphragm 21', and interposed between the sections 1;? and l-8 is a fleiiible diaphragm 22. Atthe opposite side of section 18 a flexible diaphragm-=23 isinterposed between said section and the section l9,'and still another flexible diaphragm24 is interposed be tween the section 19 anda'cover plate 25.=

"Interp'osed between diaphragms 21 and'22 is a" follower 'block"26, and contained in chamber 27 at the outer face of the diaphragm 21, is a spring 28 which urges said diaphragm toward the diaphragms 23 and 24; On one side the follower block 29 =is provided with athreaded stem 30 w hiclf extends through the diaphragm 23. Mounted :on the stem 30 is a flanged nut 31 which' clamps the diaphragm 23 against the 1501- lower block '29. v v V Coritainedin chamber 62 between the diaphragm :24 and the cover plate 25, is a pin 63, having a hea'd fi iwhich bears against the face of the diaphragm' 24 and secured-thereto by means of a suitable-cement. "fI-heshank of the pin -63 is mounted in a suitable bore 65 formed in the cover plate This provides means for 24 during the operation o'fthe devices i threaded extension '32 of the stem is mounted in a threadedbor-e of ;a stem'33. At the opposite end, thestem 33 has a head-34 for engaging the diaphragm j22-and urging the same toward the follower *block 26. i

Formed on a lug extending upwardly in chamber 66 between the diaphragms 22 and. 23,-fis a seat 39 for arslide valve 40. The slide valve is operatively mounted betweena shoulder onthe stem 33 and-the head of 'the nut 31. The purpose of theslidevalve40 is to'control communication between chamber 66 and passages '67 and 68 in the casing. V *'-Chamber 35 between'the diaphragms 21 and by said piston. 4

A spring 46 is containedjin the chamber 41 and 1 acts against a retaining. memberl47 'slidably' mounted in a nut 48 having screw-threaded 611-11;

, is arstem'56-of said piston.

22, and chamber 36 between the diaphragms 23 and 24 are permanently in communication with the atmosphere, through passages 37and 38 regagement in the casing. The downward move- I ment of the member 47 is limited by the engage-' ment of a flange 49 on said member with;the v upper face of the nut 48. I The vent valve portionof the emergency valve device 11 may comprise abrake pipe vent valve 50 contained'in-a chamber 51 and a piston 52 for, operating said vent valve. The piston 52 has a chamber 53 at oneside and achamber 54 at the opposite side, and slidably-mounted ina suitable borein the partition wall 55 of the casing The vent valve 50 has a stem 57 extending into a bore in stem 56 of the piston 52. ;The vent valve 50galso-has' a stem-58 at the opposite side extending into a bore in the'casing, said bore. containing a spring 59 which acts on the stem 58 and urges the vent valve 50 toward a seat rib 60.

Contained in the chamber-'53, is a spring 61 for maintaining the piston 52in engagement with the valve stem 57. The brake pipe 9 is connected to chamber 27 ofthe service application valve device 10, and

also to pistonchamber 41, the seat of the main slide valve 44, and vent valve chamber 51 of the emergency application valve device 11, bygapassage and pipe 69. I

The relay valve device 12 may comprise acasing' divided into sections 70, 71' and 72 Inter-- posed between the section and acover plate 73 is a flexible diaphragm 74, and interposed be-p tween the sections 70 and 71 is a flexible diaf-.'

phragm 75.; At theopposite side of section 71 a flexible diaphragm 76 is interposed between said section and the section 72,.and still another flexible diaphragm 77 is interposed betweenthe section 72 and the portion78 of the casing.:;.-".

Interposed between the diaphragms 74 {and-H5 is a follower block .79.. The: outer-face ofdiaa phragm 74 normally engages a stop lug80 which projects into chamber 81 from the cover "plate 73.

. Contained in' chamber ,82" between the dia- Phragms 75 and 76 is a'folloyverblock 83 having an intermediate shank-portion mounted -inkan opening formed in a lug 84'projecting intosaid chamber 82 from the outer wallof the section 71 of the casing. 7 At each end the-follower block 83 has wide flanges for bearingagainst the diaphragms 75 and 76 respectively. i v I A follower block 85 is interposed between the diaphragms 76 and-77. On one side the follower block 85 is provided with a threaded stem 86 which extends through ,the diaphragm -77. i Mounted on the stem 86 is a stem '87 for a slide valve 88 contained in a chamber 89. The stem 87 is provided with a flange 90 at its lower end, and the diaphragm 77 is clamped between this flange and the follower block 85. Intermediate its l n h he. tem '1 is p ovid d. With-a; second flange 91 which engages the walls of valve cham ber 89 so as to provide means for guiding the stem 87. An opening 92 is formed in the flange 91 so that valve chamber 89 is in communication with chamber 93 on the upper side of the diaphragm 77.

Chamber 89 and the seat of the main slide valve 44 of the emergency application valve device 11 are connected to the brakecylinder 7 by a passage and pipe 94.

Contained in a chamber 95 is a valve 96. At one side the valve 96 has a stem 97 which extends into. a bore in the casing, and encircling said stem is a spring. 98 which acts on the valve 96 and urges the same toward a seat rib 99. On the I opposite side the valve 96 has a stem 100 whichextends into chamber 89 and is adapted to be engaged by the upper end of the valve stem 87 during the operation of the device, as will be hereinafter described.

7 ;Valve chamber 95 of the'relay valve device 12, the seat of the slide valve40 of the service application valve device 10,- and the seat of the main slide valve 44 ofqthe emergency application valve device 11, are connected to the main reservoir 8, by passageand pipe 68.-

Chamber 101 between the diaphragms 76 and 77, and chamber 102 between the diaphragms 74 and 75 arepermanently in communication with the atmosphere, through passages 103 and 104 es c ve y-- The check valve dividedinto sections 106 and 107. .Interposed between the section 106 anda cover 108 is a flexible-diaphragm, 109 and interposed between the sections 106 and 107 is a flexible diaphragm 110. A follower block 111 is interposed between the diaphragms 109 and 110. On one side the follower block 111 is provided withv a stem 112 which, extends through the diaphragm 109 and terminatesin a bore 113 formed in the cover 108. A;--portion of-the stem 112, is threaded and mounted; on this portion of the stem is a nut 114 which clamps. the diaphragm 109 against the follower block 111.

:On the, opposite side the follower block 111 is; rojvi ded with a stem 115 which projects downwardly. through a chamber 116 and termin'ate'sfin' a suitable bore 117 in a cap screw 11'8'on thebottomof the section 107.

' The upper portionof the-stem 115 is threaded and. mounted on this portion of the stem is a nut. 1119: which clamps, the diaphragm against the follower block; 111.

Slidably mounted onthe lower portion of the stem/ is aflan'ged sleeve-like. member and. interposed between said member and the cap screw118 is a spring 121.

f Operatively mounted between the nut 119 and the sleeve 120 is a slide valve 122 which has a seat 'alonsfoneside of'the chamber 116. The slide valve 122 is maintained seated by a springpres'sed plunger 123 whichfengages the wing portion 124 of the slide valve.

' Chamber 12510151 the upper .side of the diaphragm"109 is connected to the brake pipe 9 by passage 69, heretofore described. v

Chamber 126 formed intermediate the diaphragms 109 and 110 is in constant communication with the atmosphere, through passage In operation, when a train is made up of cars provided'with the present equipment, the several-chambers', etc. willbe uncharged.

Whenfluid under pressure is supplied to the device 13 comprises a casing reservoir 8 to valve chamber 66. From chamber 66 the fluid flows to the diaphragm chamber'81 of the relay valve device 12, through passage137, and also to diaphragm chamber 82 of the relay valve device, through pasage 137, cavity 139 in the main slide valve 44 of the emergency application valve device 11, and passage 140.

" With fluid under pressure thus supplied to chambers 81 and 82 from the valve chamber 66 of the service application valve device, the pressures acting on the opposite faces of the diaphragms 74 and 75 will be balanced, and theree fore the fluid under pressure in chamber 82 acting on the lower face of the diaphragm 76 moves the parts of the relay valve device upwardly, thereby causing the slide valve 88 to be shifted and lap the atmospheric passage 136.

. left.

In the upward movement of the slide valve 88,

, the stem 87 engages the depending; valve stem 100,and lifts the valve 96 from its seat.

With the atmospheric passage 136 thus lapped by the slide valve 88 and thevalve 96 unseated, fluid under pressure is permitted to flow from the main reservoir 8 to the valve chamber 89, through pipe and passage 68, valve chamber 95 and opening 141', and from the valve chamber 89 through passage and' pipe 94, to the brake cylinder 7, thereby applying the brakes.

The brake cylinder pressure effective in chamber 66 of the service application valve device 10 acts on the right side of diaphragm 23 and on the left side of diaphragm 22. The'diaphragm 23 is larger in'area than the diaphragm 22, so

that the difference in opposing forces on said diaphragms 22 and 23 tends to deflect all of the diaphragms and shift the slide valve 40 to the When the difference in pressure acting on 1 the diaphragms 22 and 23 thus becomes suflicient to slightly overbalance the difference between the pressure in diaphragm chamber 62 acting on diaphragm 24' and the reduced brake pipe pressure in diaphragm chamber 27 acting on the diaphragm 21, the diaphragms are deflected to the left, thereby causing the slide valve 40 to be shifted and lap the fluid pressure supply passage 68, so as to prevent the further flow of fluid under pressure to the diaphragm chambers 81 and 82 of the relay valve device 12.

' At the same time that fluid under pressure is being supplied from the valve chamber 89 to the brake cylinder, through passage 94, the diaphragm chamber 93 is also supplied with fluid under pressure "from the valve chamber 89, through opening 92. v e I I As soon as the pressure of the fluid thus supplied to chamber 93 slightly overbalances the pressure of the fluid bottled up in chamber 82 on of the stem of valve 96, thereby permitting the valve 96 to seat under the action of the spring 98, so as to prevent further flow of fluid under pressure to the brake cylinder.

It is obvious from the above description of the operation of the valve mechanism in effecting a service application of the brakes, that the .degree of brake cylinder pressure obtained depends upon the degree of brake pipe reduction effected. Consequently, the brake pipe pressure may be reduced in steps and the brake cylinder pressure will build up in proportional steps,

thereby effecting a graduated application of the brakes. I I

In order to release the brakes after a service application, the brake pipe 9 is recharged with fluid under pressure. pressure is thus increased, this causes a corresponding increase in pressure in diaphragm chamber 27 of the service application valve device 10. When the pressure in chamber 27 acting on the right side of the diaphragm 21 overbalances the pressure in chamber 66 acting on the opposite side of the diaphragm 22, the diaphragms will be deflected toward the left by the higher pressure inv chamber 27, and this action shifts the slide valve 40 to the left,

thereby uncovering atmospheric passage 67.

Since the chamber 82 of the relay valve device 12 is connected to chamber 66 of the service application valve device 10 by passage 140, cavity 139 in the main slide valve 44 of the emergency application valve device 11, and passage 137, and since the chamber 81 ofthe'relay valve device 12 is also connected to'chamber 66 of the service application valve device 10 by passage 137, when the slide valve 40 uncovers the passage 67 and the chamber '66 is connected to the atmosphere, the fluid under pressure in chambers 81 and '82 will also be vented to the atmosphere through passage '67. The higher fluidpressure in chamber 93, acting on the upper face of the diaphragm 77, then deflects the diaphragms 74, 75, 76 and 77 downwardly, thereby shifting the slide valve'88 also downwardly and connecting port with atmospheric passage 136. In this way fluid under pressure is vented from the brakecylinder 7 to the atmosphere by way of pipe and passage 94,. valve chamber 89, port 135 in the slide valve 38, and atmospheric passage 136, thereby releasing the brakes.

In releasing after a service application of the brakes, the emergency valve portion .is shifted to its extreme downward position'in which the valve chamber 43 and quick action chamber 134 are recharged in the same manner as in initially charging theequipment.

If it is desired to effect an emergency application of the brakes, the brake pipe pressure is suddenly "reduced, thereby effecting a sudden reduction in pressure in the diaphragm chamber 27 of the service application valve device 10, and in the piston chamber 41 of the emergency application. Valve. device 11.

When the pressure is suddenly reduced in the diaphragm chamber 27, this permits the higher pressure in the diaphragm chamber 62 to deflect the diaphragms 21, 22, 23 and 24 to the right, thereby shifting the slide valve 40 and permitting fluid under pressure to flow from the main reservoir 8 to thechamber 81 of the relay valve device and, also to the seat of the main slide valve 44 of the emergency application valve device 11, through pipe and passage 68, diaphragm' chamber 66, and passage 137. However, since the main slide valve 44 laps the passage 137, the communication is 'cut off through which the diaphragmchamber 82 of the relay valve device 12 is'supplied with fluid under pressure from the main reservoir 8. Therefore, when an emergency application of the brakes is effected, only diaphragm chamber 81 is'supplied with fluid under pressure from the main reservoir, and the pressure of the fluid thus supplied to said chamber acting on the face of the large diaphragm 74-deflects the When the brake pipe 10, i wardly to; the extreme; upper position as shown, in Fig., 2. Thisactiorr compresses the spring. 46

.piston:.chamberf53.'.. r i

Fluid underpressurethus supplied to the vent: valve, piston chamber 5.3, shifts the piston 52.

means:

diaphragmsmi, 75; 76;.and 7J7 upwardly. Where'- uponthe partsof ,the relay: valve device are, operates, I so; as to permit fluid, under pressure to flow to the-brake. cylinder from the main reservoir manner? Similar 1 h t heretofore describ Whenthe pressure islsuddenly, reduced in the emergency piston chamber 41-, .this permits the pressurein valve; chamber 43 to shiftth'e emergencypiston 42 andslide valves 44 and 45 upand c us s: the. P ton: .2; oaea a a t the valve: piston chamber 53 for a reason to be hereinafter morefully. described.

emergencypositioniin which theport-138is disconnected from-theatmospheric passage'fi'l and connected to passage-147, so that fluid: under pressure continues to flow tothe vent valve upwardly, thereby; unseating the brake pipe ventvalve 50. This action permits fluid underpressure to be suddenlyvested from' the brake. 'pipe'9 to the atmosphere, through passage69,

vent valve chamber 51, past vent valve50 and from thence through the atmospheric chamber 150, so as to transmit serially the sudden emergency reduction in brake pipe pressure, in the usual manner. a

In the emergency position of the slide valve 1 44, fluidunder pressure in valve chamber 43 and 1 quick action chamber 134 is vented to the quick to the atmosphere through a port 151 in the quick action piston 52 and an atmospheric passage 152. By thus venting fluid under pressure only through the port 151, the piston 52 maintains the vent valve 50 unseated for a period of time sufficient to completely vent the fluid under pressure from the brake pipe.

With the emergency piston 42 and the slide valves 44 and 45 in, emergency position, the cavity 144 in the auxiliary slide valve 45 connects ports 143 and 153 in the main slide valve 44. The .port 153 registers with passage 130 from the control reservoir 131 and the port 143 registers with passage 94 from the brake cylinder 7, so that fluid under pressure is permitted to flow from the control reservoir 131 to the brake cylinder by way of cavity 144.

It will be noted that when an emergency application of the brakes is efiected, both the main reservoir 8 and control reservoir 131 are con nected to the brake cylinder, so that a high brake cylinder pressure is obtained, whereas when a service application of the brakes is effected, a brake cylinder pressure proportional to the brake pipe reduction, as governed by the Asthe piston 42 continues to move. toward. emergency position, the main slide valve 44 is; engaged by a flange 1:48'at the end of "the piston stem 149, and is thereby also moved upwardly to operation of'ptheyservice application valve: device 10: and; the relay valve device 12, is obtained. I

Moreover, the rate of build up of brake cylinder. pressure an emergency application is ,much faster than in aqservice application, since fluid under pressure is supplied. to the brake cylinder by thefloperation ofthe emergency'valve device 11, as well as, by theservice application valve device 10 and therelay valvedevice 12 r It, will furthenbe notedrthat the propagation ofiquick serial venting of fluid under pressure from the brake pipe: 9 .to the atmosphere is hastened; by' permittingfluid under pressure to. flow to the vent valvepiston chamber 53 before the main-slide valve 44 is moved, by way of port 1 1.46 in" said slide Valve and passage147. This is an. advantage, in that when the emergency piston stem flange 148 engages the main slide valve 44, therewill be a slight hesitation before the main slide valve -is moved, in order to obtain a greater difierencein pressureon the opposite sides-ofthe emergency piston 42; as requiredto move said slide valve.

Thus, during this hesitation, the vent valve.

piston chamber 53 is: partly charged with fluid under pressure, so that when the main slide valve 44is movedto emergency position thevent valve 52 will be operated at once. l

There is another advantage in supplying fluid";

under pressure to the vent valve piston chamber 53 without shifting the main slide valve from its normal position, as forinstance, if the main brake pipe pressure in order to propagate the emergency action as hereinbeiore described. 1

If for any reason, thecontrol reservoir 1131:.

becomes charged with fluid at a pressure greater than the pressure carried inthe brake pipe, than that pressure acting in; the diaphragm chamber 62 of. the service application valve device 10 will. cause. the relay valvedev-ice 12 to operate to efiect an application of the brakes in a degree proportional to the amount of overcharge or the difference in pressure in said reservoir and in the brake pipe. 'This is obvious since it is the same as if the brake pipe pressure were reduced an amount equal to the degree of overcharge.

In case the control reservoir 131 does become overcharged, then in order to reduce the pressure in said reservoir, an emergency application of the brakes is effected in the same manner as hereinbefore described. The control reservoir 131 isthereby connected to the brake cylinder 7 through the emergencyportion 11 and the pressure in said reservoir reduces by flow to the brake cylinder. The brakes may then be released and the control reservoir will then recharge to the pressure carried in the brake pipe.

It will be noted that the brake pipe 9 is only i a medium through which fluid under pressure is supplied to or vented fromthe service application value device diaphragm chamber 2'7, emergency piston chamber 41 and check valve diaphragm chamber 125, and as the combined volumes of the brake pipe and said chambers may be quite small, thepressure of the fluid therein may be varied rapidly in order to expedite the application and release of the brakes.

While one illustrative embodiment of the invention has been described in detail, it is not my intention to limit its scope to that embodiment or otherwise than bythe terms of the appended claims.

Having now described my invention, what I claim as new and desire to secure by Letters ,the brake cylinder and a chamber for operating said valve, a controlling valve, a movable abutment operated upon a reduction in brake pipe pressure for supplying fluid under pressure to said chamber, an additional movable abutment for controlling the operation of said supply valve, and an emergency valve device operated upon a sudden reduction in brake pipe pressure for controlling the operation of said additional;

abutment. I I

'2. In a fluid pressure brake, the combination .iwith a brake cylinder, and brake-pipe, of a supply valve for controlling the supply of fluid under pressure to the brake cylinder, a movable abutment subject to the opposing pressures of r a the brake cylinder and a chamber for operating said valve, a controlling valve, a-movable abutment operated upon a reduction in brake pipe pressure for supplying fluid under pressure to' said chamber, an additional movable abutment subject to the opposing pressures of said chamber and an additional chamber foralso operating said supplyvalve, and an emergency valve device normally connecting said chambers and operated upon an emergency reduction in brake pipe pressures for connecting the first chamber to the atmosphere.

3. Ina fluid pressure brake, the combination with a brake cylinder, main reservoir and brake pipe, of a valve device for controlling communication through Which fluid under pressure is supplied to the brake cylinder from the main reservoir, a control reservoir, valve mechanism subject to the opposing pressures of the brake pipe and said control reservoir for supplying fluid under pressure from the main reservoir to said control reservoir and for maintaining the pressure in said control reservoir constant except in emergency, and valve means subject to the opposing pressures of the brake pipe and said control reservoir for controlling the operation of said valve device.

4.In a fluid pressure brake, the combination with a brake cylinder, main reservoir, and brake pipe, of means operated by variations in fluid under pressure for controlling a communication through which fluid under pressure is supplied to the brake cylinder-from the main reservoir, a valve devicesubject to brake pipe pressure and the pressure in a chamber for controlling the operation of said means, and valve means govended by the opposing pressures of said brake pipe and said chamber for controlling the supply of fluid under'pressure from said main reservoir to said chamber and for maintaining a constant pressure in said chamber.

5; In a fluid pressure brake, the combination with a brake cylinder and brake pipe, of a supject' to the opposing pressures of the brake cylinder and a-chamber and the other diaphragm being subject to the pressure of fluid in said chamber and a second chamber, a valve for controlling the-supply of fluid to said first chamber, means operated upon a gradual reduction in brake pipe pressure for operating said control valve, and means operated upon a sudden reduction in brake pipe pressure for connecting the first chamber to the atmosphere and for supplying fluid under pressure to said second chamber.

JOHN N. GOOD. 

